Method of treating sugar-cane.



JOHN H. ROBERTS, CE CHICAGO, ILLINOIS, ASSIG-NOR, BY MESNE ASSIGNMENTS. TO

ZALIIION Ct. SII'LLL ONE. OF KENOSHA, \VISEfC-NSIN, ANDREW W. lR-ESlON. 0F SNA'MP- SCOTT, jlViA$i5ACHUSEiFT$ AND BRADLEY \V. PALMER. OF BOSTON. ldASSACZZUSETTS.

ma mas.

Ill-110,562.

No Drawing.

Too-ZZ whom 2'2 only com-c1 12.:

Be it known that I, done 11. llonnn rs, a citizen ot the United t tat'es, resuhng at Chicago, 111 the county of Cool; and State 01: llhnols, have invented certain new and useful Lnprovenmnts 111 Methmls at 'lreatmg Sugar-(lane, of which the it'ollo'u'ing is a specification.

This invention relates to methods of treating sugar-cane, the principal object of the invention being 'rapidand economical ccnversion'oi sugarrane, with elimination of water, into a condition of chemical stability, that to say, into a state in which it will endure prolonged storage or trans portation without material loss of its sugar content, being in this state well adapted for the recovery of merchantable sugar and other products.

My prete'rcd procedure is as follows; Sugar-cane, either 't'reshly cut or in substantially the same condition as when freshly cut, is disintegrated in such manner that the woody or fibrous and the pithy constituents are structurally dissociated from each other, the pithbeing largely converted into a granular condition somewhat resembling wet sawdust, and the woody or fibrous portions into relatively'fine shred which may taining the normal plant juices, is their vary in length from a fraction ii an inch to a foot or more, and which bear a general resemblance to excelsior. The shredding is preferably so conducted that the plant juices, in so far as they may be extruded, are completely reabsorbed in the mass. Insteadot shredding the cane in the manner above described, it may be subdivided in anyother suitable way. The subdivided cane, concharged directly into a drier, which preferably comprises an inclined revoluble cylinderhaving internal flights or lifting devices. 'lighly heated gases, usually combustion gases, are caused to flow through the cylinder in direct contact with the shredded cane, which is repeatedly lifted and droppcd through the current of gas.- Under these 1 conditions treshsurt'accs ot the moist ma terial are continuously exposed to the drying action ot the-gases, and the elimination of moisture is extremely rapid. .So long as each particle of the mass contains a considerable percentage of moisture, say in excess of six per cent.,it'is found to be entirely llliElHOD OF TREATING SUGAR-CANE.

Specification of Letters. Patent.

Application filed November 24, 1911. Serial No. 662,127.

Patented Oct. 8, 1912.

uninjured for sugaranaking purposes men when the tcmpc1atur1 ol. thcdrving gas is in excess of that at which sugar iim'lcrd ocs caramelization; and when the n'1oisturc content of the material is sullicicnlly high. it mav be exposed directly to gases haviinr a tcuipcraturc in excess of lllllll 15. without an. in ury whatever. The conditions of opera tron are such that the portions of the mass which are not otherwise removed progress regularly through the rotary drum and are continuously discharged therefrom. In orderuto minimize the dangcr'ol injurr to the material it is preferred to conduct the drying in at least two more or less dist inct stages. In the first stage the moisture content may be reduced to tu'cntv-lire per cent. 01 lower in a rotary drum in direct contact with highly heated combustion gases, the moisture content beiu thereafter further reduced in a drier of the same or other suitable type under the action of gases at a lower temperature, as for example by a cur.

system should still contain a certain proportion of moisturc,.say from two to fifteen per cent, and preferably from six to ten per cent. This residual moisture not only safeguards the sugar content of the -ane in the manner above describeljl. but by lessening the resilience of the mass, renders it possible to obtain lirmer and denser bales in presses of standard type. In some cases it is found advantageous to permit the mass to cool before baling, this cooling being accompanied by some re-absorption of moisture in case the original moisture content has been -great1y reduced. 1

111 order to avoid injury to the sugar content of the cane or to the fibers it is essential that no portion 01 the disintegrated cane, and in particular none oi" thc sugar-bearing pith cells, should be completely desiccated with high temperature material pro- 'portion of moisture-"the sugar would be inexisting in the apparatus.

velocity of the gas'fiow,

I trolled by the thermostat juriously afiected. have discovered that all irqury, even to the lightest and most minute partlcles of tissue or to the sugar associated v therewith, may be avoided by so-controlling the gas current as'to its tempera-- ture and velocity that the lighter portions of the material are blown and transported from the drier before they-are completely dried, and as fastas they approach and before theyreach a condition, moisture content, in which they would be injured by overheating atthe temperatures Such transported portions are recovered in a dust chamber or other suitable device, and either separately collected, or, 1f desired, returned to the cooler portion of the drying apparatus or to the material issuing therefrom. This procedure not only avoids injury to the'sugarbe'aringmaterial, but in case the transported portions are not returned to the drier or to the material issuing from it, it results in a direct concentration of the fibrous portions of the tissue, so thatthe product issuing from the drier contains a proportion of fibrous material to pithy matter which is higher than normal; This separation or concentration of the fibrous and pithy constitue'nts may be accentuated by increasing the and may be supplemented by I a further concentration,- by screening or otherwise, at any suitable stage of the process. I

'It. is to be understood thatthe temperature and velocity of the gas'current are adjusted not only -with reference to the removal of the lighter materials before they have been injured by overheating, but with equal reference to thecondition of the heavier portions, which should issue from the drier containing a substantial proportion of moisture, adequate for their protection-under existing temperature conditions' 'By increasing the velocity of the gas, the drying efi'ectupon all classes of the mate'rial is accentuated, while at the same time the proportion of the lighter material transported is also increased, so that this lighter material is withdrawn from the heated Zone before the moisture therein is reduced to the danger point. 7

I regulate the velocity of the gas current under substantially constant temperature conditions by a thermostatic control of the ratio between the air admitted to the furnace for purposes of combustion and the air admitted to the combustionchamber for admixture with the combustion gases, fuel adequate for the increased combustion being supplied, preferably by an automatic sicker, or other fuel-feeding device likewise coir as regards their The shredded cane having been brought to a condition of chemical stability, and if desired more or less completely separated into fractions which arericher respectively in the fibrous and pithy tissues, with their associated sugar, may,--. no w be baled for storage or transport. Preferably, but not necessarily,'the fibrous and pithy concentrates are separately baled The baling may be effected in any suitable device, or. even in an ordinary hay press." It is' desirable to con' solidate the material to a=density in excess of forty pounds and preferably approxi: mating sixty pounds per cubic foot, in which state it is practically impervious to the air or-atmospheric moisture and in all parts except the outer under highly adverse conditions.

I claim 2-- p 1. The method of simultaneously drying sugar-cane and concentrating the structural. portions thereof, which consists in subdividing the cane in such manner as to'dissociate the fibrous and pithy portions. drying the material in a current of heated gas having sufficient velocity to transport the lighter portions, and separately collecting said lighter portions.

2. The method .of' treating sugar-cane, which consists in subdividing the cane, drying the subdivided cane in'a current of gas having sufficient" velocity to transport the fecting' a further concentration of the fibrous. and pithy portions of the cane.

3. The method of simultaneously drying sugar-cane and concentrating the structural portions thereof, which consists in subdividing the cane in such manner as to dissociate thefibrous and pithy portions. drying the material in a current of heated gas having sufiicient velocity to transport the lighter portions, separately collecting said lighter portions.;and thereafter further COIlCnllIlt-'r ing the fibrous portion of. the cane.

4. The method of treating sugar-cane, which consists in shredding the cane under conditions to dissociate the bulk of the pith from the fibrous mate-rial, then subjecting the connningled mass to a tumbling operation in a current of heated gas having velocity suflicient to transport the lighter portions.

5. The method of treating sugar-cane. which consists in subdividing the cane. drying the material in a current of heated gas and controlling the gas current to remove the smaller particles from the drying cham her by the said current while they yet contain suilicicnt. moisture to protect the sugar contents thereof. 6. The method of drying subdivided sugar-cane by highly heated gases, which consists in tumbling the material progreslayer is chemically stable even lighter portions thereof, and thereafter ef- I 9'; sively through a drying chamber in a our rent of heated gas, the velocity and vohene oi" gas flow being regulated and maintained eulii'eient to hlow out and train-sport to safety, while still t'lfely-nlolsl, practically all lhoe portions wiochclosely approach a hanger- .i,-'nely-dry condition before they have pro-- gressed to a zone of safety node: the honhlmg action. v 7, The method of (ll-yen, euhd" eel sugar-cane by highly heated gases, which .eonslsts 1n tumbhng the materml progrew sively through a drying chamber in a Our rent of heated gas, the velocity and volume of, gas flow being regulated and maintained sufficient to blowout. and traneport-to sailety, whlle stlll safely-moist, practically all those portions which eloSely approach a dangermore or less constantly in a blast of gas of a temperature itar'ahove that in whirl the material could be fully dried without. in-.

jury, and so regulating the velocity and controlling, said hlaetas to blow out of the zone of i lzulgerouely high temperature, while still safelymaoietand llIlllljllJ'ttl, sueh fragments as rema" in he blast and are anproaehing a dangwmsl, dry state.

f). The process ol drying sugarcane enhdivided into fragments of varying size, whlehconsists in euhjecting the material to agitation and to a blast of highly heated gas in a, drying chamber, utilizing the change in specific gravity of the more rapidly drying 'l'ragmente lo elleet their separation and removal from the highly heated zone while still satelymloisl and in advance of the removal of the less dry frag; ments, removing the remaining"material from the highly heated zone while hlill' salielydnoiet, and emnple'ting' the drying of both fractions under lesser and safe lem-' peratnres.

JOHN H. llOlllilt'lS. W itnessee:

l lll'lC'lUlt ill. 1101131158,

ANNA, ll). hhxtouinoig.- 

